Translation:My future profession is as a doctor.
Does any other native English speaker think
"my profession is as a doctor" is incorrect? I could be wrong, but I just can't wrap my head around it. "As" is used to compare things when it is used with "to be."
You need to use a gerund here. But unfortunately "doctoring" would be equally awkward.
Take this example "my career is reporting" vs "my career is as a reporter"
But you CAN say "I work as a reporter"
Just my opinion
μέλλω is a verb meaning something like "impend, be imminent, be about to happen".
το μέλλον is the old neuter present participle ("the imminent thing, the impending thing") which has survived as a noun meaning "the future".
The stem is actually μέλλοντ- but since Greek words can't end in that cluster, the nominative is το μέλλον. The cluster (re)appears e.g. in the genitive: του μέλλοντος.
Then μελλοντικό "future (as an adjective)" is from το μέλλον, I imagine.
(Sometimes you'll also see μέλλουσα for "future (as an adjective)" when referring to a female, as in η μέλλουσα γυναίκα "the future wife (of someone)" -- this is the feminine form of μέλλον, the present participle.)